Promotion of Co/carbon sphere Fischer–Tropsch catalysts by residual K and Mn from carbon oxidation by KMnO4 Original Research Article

The effect of functionalising agents (KMnO4 and HNO3) on the surface properties of carbon spheres (CSs) produced from acetylene gas by a chemical vapour deposition method, was examined. Cobalt was loaded onto the differently functionalised CSs using the deposition precipitation (DPU) method and the Co/CS catalysts were tested for Fischer–Tropsch (FT) activity. FT studies, revealed differences in activity and selectivity for the HNO3 and KMnO4 functionalised catalysts. Investigation of the role of Mn (0.05%) and K (0.05%) on Co/CS FT catalysts functionalised with HNO3 revealed that these differences were due to the presence of residual MnO4− ions remaining after the surface functionalisation reaction.